The present invention relates to a machine for fitting and removing wheel tyres for vehicles.
It is known that vehicle wheels generally comprise a metal rim having, along its perimeter, annular flanges among which are inserted in tight abutment the end portions, so-called “beads”, of an elastic tyre.
The use of machines is currently known, so-called “tyre-changing machines”, able to remove and fit the tyre from the relevant rim e.g. for running maintenance, repair or replacement jobs.
Different types of tyre-changing machines of the automatic type are particularly known which generally comprise a base having an attachment and rotation arrangement for attaching and rotating a wheel, one or more supporting uprights which rise vertically from the base, a tool-holder assembly associated with the upright and movable in translation at a height and horizontally, either manually or by the action of respective actuators, having one or more tools for removing the tyre.
One of the removal tools commonly has a curved end part and is used to grasp the tyre bead and to lift and take it off above the annular flange of the rim. Other tools, generally supported by suitable auxiliary arms, are used to assist the operator during all the tyre fitting and removal operations.
The tyre-changing machines of known type have, however, some drawbacks.
In fact during use, the operator uses different tools intended for bead breaking, extraction and positioning of the tyre bead from/onto the rim edge, the removal or positioning of the tyre from/onto the rim.
This necessarily entails a continuous manual adjustment by the operator of the position of these tools depending on the specific dimensions of the wheel, resulting in considerable lengthening of the overall fitting/removal times.
Moreover, the need to carry out such continuous manual adjustment increases the chances of a positioning error by the operator, with the consequent possibility of damaging the tyre and the rim.